It is known in the art to treat chickens with copper in order to improve their weight gain and to prevent nutritional anemia. The copper requirements of chickens is described in M. O. North and D. D. Bell, "Commercial Chick Production Manual," Chapman & Hall, p. 599, 4th Ed., 1990, as follows:
Nutritional anemia occurs when there are deficiencies of copper and iron in poultry's diet. The red blood cells contain iron. The mineral also is needed to pigment the feathers of certain breeds of chickens. Copper is necessary for iron utilization when hemoglobin is formed; therefore, if absent from the diet, anemia results. The amount of iron and copper needed in the diet of the chicken is quite specific; excess may be toxic. About five to ten times as much iron as copper is required. Usually, only small amounts, if any, are ever added to the feed formula. PA1 Iron is not fully utilized, however, without available copper and cobalt. For these reasons copper sulfate and cobalt sulfate became pans of the original composition. It has subsequently been determined through continuing research that the choline citrate compounds of copper and cobalt are far more desirable in that they are less toxic, more readily available, and therefore, serve more adequately to enhance absorption and utilization of the iron than do the inorganic compounds, thereby greatly stimulating hemoglobin rise and increased red blood cell counts. PA1 The chick's demand for choline is great. Choline forms a part of the phospholipid, lecithin, rather than an enzyme. Therefore, choline is seldom considered a true vitamin. At times it may be synthesized by the chick, but the amounts are small and usually inadequate. The older a bird gets, the better the synthesis. PA1 The vitamin has a great many functions in the body: It helps in fat movement in the bloodstream; it has a sparing action on methionine; it aids in growth; it prevents a type of slipped tendon; and it helps to reduce excessive fat deposits in the liver.
Generally, copper sulfate is administered to the chickens by mixing or dry blending it in with their daily feed, which typically comprises corn and soybean meal. A typical prior art chicken feed with blended copper sulfate is prepared by dry blending one to two pounds of copper sulfate with one ton of chicken feed. The copper sulfate is therefore administered to the chickens at a rate of 125 ppm -250 ppm copper metal equivalent.
Although the copper sulfate produces improved weight gain in chickens compared to untreated chickens, any further improvement would be of tremendous value to the poultry industry. Furthermore, the copper in the copper sulfate is excreted by the chickens in their feces. This produces a significant disposal problem for chicken ranchers.
U.S. Pat. No. 3,231,466 relates to a composition for treating animals, including poultry. This patent discloses that the composition enhances the growth response and/or the general health of domesticated animals. The composition comprises iodine in an organic form, either choline iodine or ethylene dihydroiodide; phthalylsulfacetamide; and iron, cobalt and copper in the form of choline citrate complexes. The patent further discloses that:
Although this patent discloses copper choline citrate, it is apparent that the focus of the invention was on the addition of choline to the composition; not the addition of copper in a citrate form.
Choline is known to be an aid to the growth of chickens. As disclosed by M. O. North and D. D. Bell, "Commercial Chick Production Manual," Chapman & Hall, p. 599, 4th Ed., 1990:
In view of this prior art, one would expect that the removal of the choline from the copper choline citrate complex would not produce an improvement in the growth of poultry.
Therefore, a need exists for a feed supplement which produces less toxic waste while maintaining or improving the weight gain of chickens treated therewith. Furthermore, there is also a need for a form of copper which enhances the growth response of poultry, but which does not include choline as a complex with copper.